Firebox door



June 25, 1935.

T. E. LAYDEN FIREBOX DOOR Filed June 5, 1933 II/I/IIII Patented June 25, 1935 Thomas Layden, Topeka, Kans.

Application June 5, 1933, Serial No. 674,368

.2 Claims.

My invention relates to doors for locomotive fireboxes and particularly to the fireboxes of locomotives which burn fuel oil; the principal object of the invention being to provide a firebox door whereby a controllable quantity of air may 4 be admitted, in a prearranged manner, to the firebox in keeping with the operating conditions of the locomotive.

One object of my invention is the provision of a construction whereby the air will be admitted in a plurality of separate streams. of relatively high velocity, so as to flow toward the forward end of the firebox and hence penetrate the rising column of vapors and burning fuel to a considerable distance and thus bring about the desired diffusion of air'and oil vapor and promote complete combustion in the firebox.

Another object of the invention is the provision of a construction whereby the air may be or to the hazard of personal injury from fire,

' steam, or hot water escaping through the opening of the fire door in the event a rivet, flue, staybolt or other part of the internal construction of the boiler should become defective or fail and allow steam or hot water from the boiler to be discharged into the firebox.

The above enumerated objects as well as other objects and advantages inherent in the invention will all be readily comprehended from the following detailed description of the accompanying drawing wherein:-

Figure 1 is a vertical sectional view of the firebox end of an oil burning locomotive provided with my invention. a

Figure 2 is an enlarged vertical sectional view of my improved fire door..

Figure 3 is a cross sectional view taken substantially on the line 33 of Figure 2 looking in the direction of the arrows. 1

As my invention'is especially intended for locomotive fireboxes, the fireboxend of an oil burn-. ing type of locomotive is shown consisting of theusual outside sheet or casing l0, firebox H, the forward end whereof is provided with the usual fiues l2; the firebox and fiues being completely submerged or surrounded by water under normal working conditions.

The opening at thebo-ttom of the firebox is enclosed by the usual fire pan 13 which is lined with brick or other suitable refractory material; and disposed transversely of the fire pan and of the firebox is a heavy wall of refractory brick as shown at' I4, extending upwardly to approximately the level of the door opening in the firebox, see Figure 1.

The forward end of the fire pan I3 is provided with an opening I5 through which the oil burner or atomizer l6 projects. The burner or atomizer I6 is arranged centrallyin the opening I5 in order that the remainder of the opening may be left clear to admit air for combustion and also to keep the/burner from becoming overheated. The burner or atomizer l6 is adapted to provide a jet of finely atomized fuel oil mingled with dry steam; and this jet is projected in the combustion spaceand against the transverse wall M in the form of a spray. f

The bottom of the fire pan I3 is provided with an opening I'l; While the opposite sides of the fire pan are provided with series of annular openings IB, for the purpose of admitting the major portion of the air required for combustion. I

The fire door opening in the rear walls of the fireboxand the boiler is formed in a well known manner and the opening surrounded by a suitable frame !9, to which my improved fire door 20 .is hingedly connected in the usual manner as shown at 2| in Figure3. I

The fire door 20 is made hollowin construction to permit the passage of air through the interiors of the door; and the hollow space 22 inside the door 20 is adapted to be in open com-,

munication with the upper end of an air duct 23; I The lower end of the fire door 20 or rather the communicating opening at the bottom of the door is preferably made to conform to the shape of the passage through duct 23 and regis-.

ters with the upper end of this duct when the door is in closed position as shown in Figures 1' and 2.

The duct 23 is rigidly fastened in any suitable manner to the boiler back head so as to provide sufiicient clearance between the lower edge of the door 20 and the duct 23, to permit the door to swing on its, hings 2| without interfering carry a liner 25 which is adapted to project a considerable distance through the door opening into the firebox. In the particular exemplification the door is shown provided with inturned flanges at 26, along opposite sides, see Figure 3;

and the liner 25 along its sides is shown flanged at 21 arranged in lapping relation with the door flanges 26 and thus maintain liner 25 in place.

The liner 25 is in the nature of an open' ended cit ' the admission of greater quantities of air, does not provide for the necessary diifusion of the' zle-shaped passages 29 are provided. That is to say, the liner 25 preferably is made to provide two or more nozzle-shaped passagesthrough which air from the interior of the door 20 may pass into the combustion space of the firebox.

The air inlet end of the liner 25 is provided with a damper 30 mounted on a transverse shaft 3|, one end whereof is provided with an operating lever 32. The damper 30 is adapted, when in closed position, to cover practically all of the inlet ends of the nozzle passages 29; although in practice the damper 3!! is usually arranged to admit a small amount of air when the damper is closed. The purpose of this air admission is to cool liner 25 and prevent the inner or nozzle ends of the liner from burning off.

The lever 32 is rigidly secured to shaft 3| so the latter will rotate and swing the damper 30 from its closed position shown in full lines into.

an open position as shown in dotted lines in Figure 2. The lever 32 is disposed along aside of the door and the latter is provided with a slot ted ear as at 33 to receive a threaded pin'on lever 32 which, on the opposite side of ear 33, is provided with a clamping member 34, whereby lever 32 andshaft 3|, with damper 30 are held in thedesired open position., v v

The operation of my improved air admitting fire door is as follows: r

At low rates of firing, all'of the air necessary for proper combustion of fuel oil may be supplied through openings l5, lland I8 .in the fire pan,which are usually proportioned sothat they" will supply all of the air necessary for ordinary operation. Under these conditions, the damper'is kept in closed position.

However, when the'locomotive is working at its maximum capacity, or when the locomotive enters a higher altitude, the amountof air, admitted through openings l5, H and I8, which was sufiicient at low rates of firing, orat low altitudes, becomes insuflicient and more air, properly-diffused with the vaporized andburning fuel, must be admitted to maintain proper combustion. i i

It is known to be a fact, that the enlarging of openings I5, I! and I8, while providing for air with the rapidly vaporizing and burning fuel that is sprayed into the firebox.

Under conditions of maximum firing rates, the column of vaporizing and burning oil spray passes out of the combustion zone adjacent to openings I! and I8 before vaporization is'completedn It is therefore necessary to admit an auxiliary supply of air higher up in the firebox in order to obtain'and realize the proper diffusion of air with the fuel attending or involved in this-delayed vaporization. This is accomplished with my improved fire door, through the open ing of damper 30, thereby admitting a suitable amount of air through the nozzle openings or passages 29 of the liner, 25.

When a locomotive is working at, or near its maximum capacity, a partial vacuum exists in the firebox and this partial vacuum causes the air vadmitted by my improved fire door to flow through the nozzle openings or passages 29 at a high velocity. By reason of the construction of myimproved' air. introducing means and the velocity of these incoming streams of air, the air streams are caused to fiow forwardly and to penetrate to a considerable distance into the rising column of vapors and burning fuel thus inducing andbringing about the desired diffusion of air and oil vapor and hence promoting complete combustion.

-It is apparent that with oil burning locomotives as heretofore constructed, while operating under maximum firing conditions, a thorough and complete combustion is not obtained, because the vaporizing and burning oil sprays pass out of the combustion zone at the lower part of the firebox adjacent to the usual air admitting openings. In order to promote proper combustion it is neces-. sary therefore to provide means whereby regulable and controllable quantities of air can be introduced so as to be properly diffused and where it will commingle with and diffuse the-rising column of vapors and burning fuel and consequently greatly enhance the efiiciency of the locomotive.

The drawing illustrates a simple embodiment. of the invention and the exemplification has been described in terms employed merely. for'purposes of description, as structural modifications are possible and may be made without, however; departing from the spirit of myinvention;

, 1. Ina locomotive firebox, the combination'of a hollow fire-door openat the-rear .to the. firedoor opening of the firebox and terminating "at the bottom in .a downwardly disposed. open por-. tion whereby air is admittedinto thechamber of the door; a fixedly-secured conduit member arranged to register :with the lower end of said door portion when the dooris closed; an open ended shell member mounted at one end on the rear side of the door so as totextendinto the door-opening of the fire-box,,the discharge end of said member having a plurality of rearwardly diverging passages arrangedside by side and spaced apart, while the other end of the shell member com municates with the air chamber in the door; a

damper pivoted in the upperpart of the chamber in the door and arranged to extend across the inletend of the shell; and'means extending to the door exterior for manually controlling said damper whereby flow of air from the chamberin the door and through said passages may be regulated.

2. In a locomotive firebox, the combination of a hollow fire-door open at the'rear to the firedoor opening of the firebox and. terminating at bottom in a downwardly disposed duct portion coextensive with the width of the door whereby air is admitted into the chamber of -the--door; a fixedly secured conduit member arranged with one of its ends registering with the lower endof said duct portion when the door is closed; an

open ended frusto-conical shell member mountedat its large end on the rear side of the door'with the other end disposed through the fire-door opening, the shell interior having a vertically ex'-'- tending partition, V-shape in cross section, so fas to provide rearwardly divergingpassages coextensivewith the inner vertical dimensions of the shell; a damper-pivoted in the upper part of the chamber inthe door and adapted to extend across the upper portion of the inlet' end of the ;shell;

an operating lever arranged on the doorexterior for controlling the damper; and means. carried by the door for locking the lever in its adjusted, 

